http://www.lp.org/article_85.shtml
This is the Libertarian party's official website FAQ that answers your question about them. I like their platform and sometimes vote for their candidates, but I have never seen a candidate that hews to the full party platform. Usually they pick and chose what parts of the platform they run on.
The Independent Party as a group are not independent voters as I answered your question earlier, and bear no relation to my answer to your previous question. There are several different groups that call themselves the Independent Party, but this is the only group that I see that defines independent voters the same as I have in my previous answer: http://www.yale.edu/ip/ They are not a political party as such since they do not have candidates that run for elected office.
You will have to pick a particular Independent Party to receive an answer as to their beliefs, since they all have their own platforms and agendas.